Revenues (Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Noncurrent receivables origination in 2020	$ 1,020
Noncurrent receivables origination in 2019	608
Noncurrent receivables origination in 2018	299
Noncurrent receivables origination in 2017	82
Noncurrent receivables origination prior to 2016	15
Other Assets [Member]
Disaggregation of Revenue [Line Items]
Noncurrent receivables	$ 2,020	$ 2,150

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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Amount of financing receivable originated more than five years prior to current fiscal year.

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Amount of financing receivable originated in current fiscal year.

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